The French conquest of Algeria took place between 1830 and 1903. In 1827, an argument between Hussein Dey, the ruler of the Regency of Algiers, and the French consul escalated into a blockade, following which the July Monarchy of France invaded and quickly seized Algiers in 1830, and seized other coastal communities. Amid internal political strife in France, decisions were repeatedly taken to retain control of the territory, and additional military forces were brought in over the following years to quell resistance in the interior of the country.

The Regency of Algiers was a largely independent tributary state of the Ottoman Empire during the early modern period, located on the Barbary Coast of North Africa from 1516 to 1830. Founded by the corsair brothers Aruj and Hayreddin Barbarossa, the Regency was a formidable pirate base infamous for its corsairs. First ruled by Ottoman regents, it later became a sovereign military republic that plundered and waged maritime holy war against European Christian powers.